Based on the reversible heat engine model, theoretical analysis is carried out for economic performance of a solar tower power plant (STPP) combined with multi-effect desalination (MED). Taking total revenue of the output power and the fresh water yield per unit investment cost as the economic objective function, the most economical working condition of the system is given by analyzing the influence of the system investment composition, the receiver operating temperature, the concentration ratio, the efficiency of the endoreversible heat engine, and the relative water price on the economic parameters of the system. The variation curves of the economic objective function are given out when the main parameter is changed. The results show that the ratio of water price to electricity price, or relative price index, has a significant impact on system economy. When the water price is relatively low, with the effect numbers of the desalination system increasing, and the economic efficiency of the overall system worsens. Only when the price of fresh water rises to a certain value does it make sense to increase the effect. Additionally, the threshold of the fresh water price to the electricity price ratio is 0.22. Under the conditions of the current price index and the heliostat (or reflector), the cost ratio and the system economy can be maximized by selecting the optimum receiver temperature, the endoreversible heat engine efficiency, and the optimum concentration ratio. Given the receiver surface temperature and the endoreversible heat engine efficiency, increasing the system concentration ratio of the heliostat will be in favor of the system economy.

Efficient thermal management of lithium-ion batteries is crucial for electric vehicle safety and performance. This study investigates immersion cooling in serpentine channels for 18650 batteries, aiming to identify key factors affecting maximum battery temperature (Tmax) and pump power (Pw). A Box-Behnken experimental design is implemented with Computational Fluid Dynamics simulations to analyze responses Tmax and Pw. Five design variables are defined: partition length (Lp), battery charging/discharging rate (Crate), coolant volumetric flow rate (V), coolant inlet temperature (Tin) and ambient temperature (Tamb). Statistical significance is evaluated via Analysis of Variance. The results show that: Tin dominated Tmax, followed by Crate, V, and Lp. Significant interactions (V·Tin and V·Tamb) are observed. For Pw, V and V² show extreme significance, while Lp effects were minor. Interaction Lp·V was significant but secondary. After optimization to minimize Tmax, Tave and Pw, the optimal design values for Lp, Crate, V, Tin, and Tamb were determined to be 89.5 mm, 1.08 C, 0.51 LPM, 20 °C, and 25.62°C respectively. The corresponding optimized values are: Tmax = 22.87°C, Tave = 21.67°C, and Pw = 0.279 mW. Optimal thermal management requires prioritizing Tin control for temperature suppression and V regulation with non-linear compensation for energy efficiency.

The hollow fiber membrane humidification modules are used for indoor humidification in hot–dry regions and heating in winter. The module is composed of several flexible hollow fiber membranes, which are bent and displaced by gravity and fluid forces. This paper is a further study of previous work that reveals the internal relationship between the forces generated by vortex shedding and fiber vibration. The central trajectories of fibers in the flow field are described for various pulsating flow and fiber structure parameters. The effects of fiber displacement on fluid flow, heat transfer, and mass transfer performance at different parameters are discussed. The results show that the fiber displacement in the flow field consists of two components: (i) deformation caused by fluid drag force and gravity and (ii) periodic vibration caused by periodic lift and drag force as vortices shed at the fiber surface. The fiber vibration facilitates the vortex shedding on the fiber surface, which enhances the convective heat and mass transfer performance on the fiber surface. The average friction factor (f_m,v), Nusselt number (Nu_m,v), and Sherwood number (Sh_m,v) increased by 12.9%, 39.3%, and 20.0%, respectively, when the fiber vibrated compared to non-vibration. This implies that inducing fiber vibration can optimize the heat and moisture transfer performance.